#define _CRT_SECURE_NO_WARNINGS
#include <iostream>

using namespace std;

string modifyString(string s) {
    for (int i = 0; i < s.size(); ++i)
    {
        if (s[i] == '?')
        {
            for (char c = 'a'; c <= 'z'; ++c)
            {
                s[i] = c;
                if ((i == 0 || s[i - 1] != c) && (i == s.size() || s[i + 1] != c))
                    break;
            }
        }
    }
    return s;
}
int main()
{
    modifyString("?zs");
	return 0;
}